Bumping gaia.json for 2 gaia-central revision(s) a=gaia-bump

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https://hg.mozilla.org/integration/gaia-central/rev/be86ac21caa5
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Merge pull request #12801 from KevinGrandon/bug_924274_add_contacts_tests

Bug 924274 - [Contacts] Add marionette tests r=arcturus, jmcf

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https://hg.mozilla.org/integration/gaia-central/rev/6c141a3c6e90
Author: Kevin Grandon <kevingrandon@yahoo.com>
Desc: Bug 924274 - [Contacts] Add initial marionette tests